JP3489862B2 - Analog clock - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for driving a step motor for a high-speed analog chronograph, which starts, rotates, and stops a high-speed analog chronograph step motor at a constant speed.

[0002]

2. Description of the Related Art As shown in FIG. 6, a step motor 601 for a conventional analog chronograph has a two-pole rotor 602.
And a two-pole stator 603 and a drive coil 604. A block diagram of a drive circuit of a step motor for an analog chronograph of a conventional wristwatch with an analog chronograph shown in FIG. 3 will be described along with a time change of each pulse of the conventional example shown in FIG. First, when the analog chronograph is started, the start / stop signal generating means 30
4A, a start signal 401 shown in FIG. 4A is generated, a reference signal generating means 302 generates a reference signal 403 having a constant cycle shown in FIG. 4B, and a drive pulse generating means 303. Generates a drive pulse 404 having a constant pulse width, which is synchronized with the rising or falling of the reference signal 403 shown in FIG.
Is input to the driver 304, and the driver 304 drives the step motor 601 to rotate the step motor 601 at a constant speed to move the analog chronograph hands engaged with the rotor of the step motor via the train wheel. , Stop signal 40 when the analog chronograph is stopped
2 is generated, the generation of the drive pulse 404 is stopped, and the step motor 601 is stopped.

[0003]

However, the above-mentioned constant drive pulse width 404 is determined by an experiment and cannot be applied to any use environment of a wristwatch. For example, when the wristwatch is worn on the wrist. When the arm is swung back and forth during running, acceleration is applied to the rotor of the step motor, and inertia torque generated in the rotor due to the acceleration may prevent normal start, rotation, and stop of the rotor. Further, since the rotational position of the rotor is detected and the drive in synchronization with the rotational position signal, that is, the synchronous drive is not performed, the rotor cannot be optimally driven, and therefore the rotational speed of the rotor is 3 at most.
Only 000 rpm was raised. By the way, a Seiko TIME C that drives a chronograph step motor by the conventional method of driving a step motor described above.
ORP. The 1/100 second chronograph wristwatch made in '92
Released in the year.

The present invention is excellent in use environment, and can be normally started, rotated at a constant speed and stopped even during running, etc., and the rotation speed of the rotor is 6000 rpm (1/2).
A watch with a 00-second chronograph is possible) An object of the present invention is to provide a reliable watch with a high-speed analog chronograph equipped with a step motor.

[0005]

To achieve the above object, the present invention provides an analog having a step motor having a drive coil, a stator and a rotor, and drive pulse generating means for supplying a drive pulse to the drive coil. In the watch, a rotor position detecting means for detecting the position of the rotor is provided.
The drive pulse generating means is provided for detecting the rotor position.
Based on the output of the means, the output type of the stop pulse with a large effective power output at the end of driving the step motor.
It is characterized by controlling the minging . In addition, the drive
The loose generating means outputs the stop pulse before outputting the stop pulse.
Effective voltage for switching only the rotor steering state
It is characterized by outputting a pulse having a small force.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 5, the step motor 501 for the high speed analog chronograph of the present invention is a two-pole rotor 5.
02, a two-pole stator 503, a drive coil 504, and a rotor magnetic pole position detection coil 505 for detecting a magnetic pole position θ506 (0, π) of the rotor 502.

A block diagram of the drive circuit of the step motor for a high speed analog chronograph of the present invention shown in FIG. 1 will be described along with the time change of each pulse of this embodiment shown in FIG. First, as shown in FIG. 2 (a), when to start the analog chronograph start / stop start signal 201 from the signal generating means 101 is generated, by the start signal 201, a predetermined period from the reference signal generating means 102 The reference signal 203 is generated, and the driving pulse generating means 105 causes the stepping motor for the high-speed analog chronograph to have a two-pole rotor 502 for at least two driving pulses from the generation of the start signal 201.
Since it has a two-pole stator 503,
Corresponds to one rotation. ), As shown in FIG. 2 (d ), a drive pulse synchronized with the reference signal 203 and having a constant pulse width,
Start pulses 208 and 209 are generated. At least when the position detection signal 205 generated by the position detection signal generating means 103 shown in FIG. 2 (c ) is delayed from the reference signal 203 by the phase difference φ1 from the third driving pulse, the phase comparing means Based on the output corresponding to the phase difference φ1 of 104, the drive pulse 210 having a pulse width T2 wider than the pulse width T1 of the drive pulse 209 immediately before is generated in synchronization with the rising of the position detection signal 205. The drive pulse 210 causes the driver 106 to accelerate the rotor 502. Similarly, the position detection signal 2
When 06 leads the reference signal 203 by the phase difference φ2, the pulse of the immediately preceding drive pulse 211 is synchronized with the rising edge of the position detection signal 206 based on the output corresponding to the phase difference φ2 of the phase comparison means 104. Compared with width T3 ,
A drive pulse 212 having a narrow pulse width T4 is generated. As described above, the drive pulse generating means 105 synchronizes with the rising or falling of the position detection signal 204 when the position detection signal 204 lags the reference signal 203 based on the output of the phase comparison means 104. Then, a drive pulse having a wider pulse width than that of the immediately preceding drive pulse is generated, and when the position detection signal 204 advances with respect to the reference signal 203, it synchronizes with the rising or falling of the position detection signal 204. Then, a drive pulse having a pulse width narrower than the pulse width of the drive pulse immediately before is generated to rotate the rotor 502 constantly. When the analog chronograph is stopped, start / stop signal generating means 1
As shown in FIGS. 2A and 2D by 01, when the stop signal 202 whose rising edge is within the generation time of the drive pulse 213 is generated, the drive pulse 21 is generated.
Steering for switching the direction of the current flowing through the drive coil 504 based on the drive pulse 213 of the driver 106 in synchronization with the first rising (or falling) of the position detection signal pulse 207 after the end of Step 3. The first stop pulse 214 having a pulse width sufficiently shorter than the pulse width of the immediately preceding drive pulse that does not contribute to the rotation of the rotor and the first stop pulse 21 immediately after the first stop pulse 214.
A stop pulse 216 composed of a second stop pulse 215 having a pulse width sufficiently longer than the pulse width of 4 is generated, and the polarity of the magnetic pole of the rotor 502 and the magnetic pole of the stator 503 facing the magnetic pole of the rotor Are held at different polarities to brake the rotor 502 and forcibly stop the rotor 502 without causing it to escape. Here, the position detection signal pulse 207 is a multi-pulse because the rotor makes a damping vibration when the rotor is stopped. On the other hand, the stop signal 20 does not rise at the time when the drive pulse 213 is generated.
When 2 ′ occurs, the steering wheel of the driver 106 is inverted in synchronization with the first rising (or falling) of the position detection signal pulse 207, and the pulse width of the immediately preceding drive pulse that does not contribute to the rotation of the rotor. First stop pulse 21 with a pulse width sufficiently shorter than
4 and immediately after the first stop pulse 214, a stop pulse 216 including a second stop pulse 215 having a pulse width sufficiently longer than the pulse width of the first stop pulse is generated to generate a magnetic pole of the rotor 502. By holding the polarities of the magnetic poles generated in the stator 503 facing the magnetic poles of the rotor at different polarities, the rotor 502 is braked and the rotor 502 is forcibly stopped without escape.

As is apparent from the above description, in the step motor driving method of the present invention, the phase is controlled so that the phase difference between the rotor position detection signal and the reference signal becomes zero. Optimizing the rotor,
Since the rotor rotates at a constant speed, the number of rotations of the rotor can be improved compared to the conventional driving method. It starts, rotates, and stops, and the analog chronograph hands can operate and stop normally at high speed.

[0010]

INDUSTRIAL APPLICABILITY The present invention is excellent in use environment and can be normally started, rotated at a constant speed, and stopped even during running.
Also, the rotation speed of the rotor can be 6000 rpm (1 /
A wristwatch with a 200-second chronograph is possible). It is effective in providing a reliable high-speed analog wristwatch with a chronograph equipped with a step motor.

[Brief description of drawings]

FIG. 1 is a block diagram of a drive circuit for a high-speed analog chronograph step motor according to the present invention.

FIG. 2 is a time change of each pulse in the present embodiment.

FIG. 3 is a block diagram of a drive circuit of a chronograph step motor of a conventional wristwatch with an analog chronograph.

FIG. 4 is a time change of each pulse in the conventional example.

FIG. 5 is a plan view of a step motor for a high speed analog chronograph according to the present invention.

FIG. 6 is a plan view of a conventional step motor for analog chronograph.

[Explanation of symbols]

101 Start / Stop signal generating means 102 reference signal generating means 103 Position detection signal generating means 104 Phase comparison means 105 Drive pulse generating means 106 driver 203 Reference signal 204 205 206 207 Position detection signal 208 209 Start pulse 210 211 212 212 213 Drive pulse 214 First stop pulse 215 Second stop pulse 216 Stop pulse

Claims (2)

(57) [Claims] 1. An analog timepiece having a step motor having a drive coil, a stator and a rotor, and drive pulse generation means for supplying a drive pulse to the drive coil, and rotor position detection means for detecting the position of the rotor.
And the drive pulse generator is configured to detect the rotor position.
Based on the output of the output means, the output pulse of the stop pulse with a large effective power output at the end of driving the step motor .
An analog timepiece that controls imming . 2. The analog timepiece according to claim 1 , wherein the drive pulse generating means outputs a pulse of small effective power for switching only the steering state of the rotor prior to the output of the stop pulse.